1. Technical Field
This application relates to a device for the separation into lots, spacing and grouping of packaged goods, boxes, workpieces or items such as bottles, cans and similar containers with a conveyor, on which a stream of items is guided and with separating elements that interact with said conveyor and can be moved so that they are engaged at a predetermined spot on the conveyor behind or between the packaged goods and separate said packaged goods into individual units, rows or groups, whereby the distances between the separating elements are variable, and different group sizes can be created and the separator elements or separator fingers are held on conveyors or conveyor chains that preferably circulate independently of the item conveyor.
2. Background Information
In the field of industrial manufacturing there are numerous situations in which products that have been assembled into units for production or consumption or bottled products must be combined into larger units for transport, distribution or sale. In the beverage industry in particular, a large number of bottles, cans and similar containers must be packed into cases, boxes, trays or shrink-wrap. For the performance of these packing tasks, most of which are performed by case packers, packing or palleting machines, it is necessary to separate a stream of products that are preferably delivered to the packing machine continuously into groups or formations of defined sizes, as a function of their subsequent position in a package or on a pallet. In this context, it is necessary to position the items at the proper spacing and to achieve an appropriate synchronization of the formatted or individual packaged goods in relation to the specified machine cycle. The prior art describes a number of different devices that perform this task.
For example, DE-PS 30 29 508 describes a device for the grouping of large numbers of bottles for packing in cases or boxes and similar containers. To make it possible to process different items and package sizes, between the packing machine and the delivery conveyor belt there is a grouping device that has a plurality of rods that are mounted so that they can move radially with respect to a drive shaft, and on the ends of the rods there are separator fingers which extend into the moving stream of articles and separate it into appropriate groups of items. The separator fingers are also controlled by a circulation guide. For the creation of different package sizes, both the drive shaft and the circulation guide can be adjusted and moved, so that the point at which the separator fingers are inserted into the flow of items and the point at which they emerge from the separated group of articles are defined synchronously by the simultaneous adjustment of the drive shaft and of the circulation guide. To make the adjustment, the drive shaft is adjusted so that it is perpendicular with respect to the conveyor belt and the circulation guide is simultaneously spread or placed over it like a mushroom. One disadvantage of this device of the prior art is that the separator fingers, during the separation of the groups of articles from the flow of items, is subjected to sudden and significant changes in velocity and acceleration, as a result of which the articles are not automatically able to track the movement of the separator fingers and consequently execute uncontrolled movements or bump against each other and can even fall or be knocked over.
In the context of this application, the term “separator finger” which is used throughout the application means all the elements that are inserted into a product stream to separate it into lots, group or batches, to break up the flow or to position the individual products. The separator fingers can be elements that are pin-shaped, rod-shaped or any other shape, and can be inserted into the product flow from above, below and/or from a lateral direction.
DE-PS 34 14 607 also describes a corresponding device of the prior art that works according to a comparable principle. As a result of the additional presence of drag levers in combination with an external rotating wheel and a non-adjustable circulation guide, it is possible to operate the separator fingers at a more uniform velocity. However, this device is very complex and expensive in terms of its construction, as a result of the large number of additional components.
Another device for the grouping and spacing of items is described in DE 298 16 128 U1. The means of transport for the separator fingers is a flat link articulated chain, the length of which is variable.
In contrast to the conventional construction of flat link articulated chains, in which the connecting pins to the respective neighboring links of the chain are mounted in borings, the links of the flat link articulated chain taught by this prior art document have slots on one side. The distance between the connecting pins of a chain link can be reduced by means of these slots, which also results in a reduction of the overall length of the chain.
To make a change in the length of the flat link articulated chain, the chain links have control lugs that project laterally outward and are engaged in the threads of a feed screw or worm conveyor that determines the pitch only or independently. This feed screw can be driven in synchronization with the conveyor chain, and over its effective length defines the speed of transport of the drivers and also the distance between them, as well as their spacing. In this context, it should be noted that the shortening of the flat link articulated chain can be effective only in the vicinity of the feed screw.
One disadvantage of this device of the prior art is the unstable behavior of the individual links and their slots with respect to one another, and the resulting noise that is generated continuously, as well as the inevitably increased wear on the components used. These disadvantages cannot be overcome even by special coating measures to reduce the amount of noise that is generated by components that come into contact with one another during operation. A further disadvantage is the rigid definition of the distance between the individual groupings as a result of the fixed pitch of the conveyor groove or of the thread of the conveyor screw, as a result of which any change in the distance between groupings requires a replacement of the conveyor screw, which is a complex, time-consuming and expensive operation.